Ultra-low expansion quartz glass (ULE) is a special material with a coefficient of thermal expansion (CTE) of 10-9/℃, achieved through precise TiO2 doping. It boasts excellent dimensional stability and temperature adaptability, making it widely used in astronomical observations, laser detection, and semiconductor manufacturing. During the preparation of ULE materials, the uniformity of TiO2 distribution affects the uniformity of CTE distribution, which in turn significantly influences the optical surface figure and the stability of imaging quality of ULE optical components. Therefore, ensuring full-bore CTE homogeneity in ULE materials has become a key focus in material preparation technology research, among which highprecision measurement of CTE and its uniformity provides strong support for efficient iterative optimization of the material preparation process. This paper provides a comprehensive review of the preparation methods of ULE and its CTE control mechanisms, focuses on analyzing the research progress on detection technology of CTE and its uniformity, and compares the advantages and disadvantages of each technology: Traditional sampling calibration methods, such as the pushing-rod method, interferometry, and photoelasticity, can achieve high-precision measurements but have limitations such as destructiveness and complex operation; while nondestructive testing methods (such as the refractive index method, the linear focused ultrasonic scanning method and the ultrasonic longitudinal wave velocity method) provide effective solutions for full-bore CTE evaluation of ULE materials. In particular, the ultrasonic longitudinal wave velocity method can effectively characterize CTE and its uniformity in large ULE boules, and achieve a good balance between measurement accuracy and engineering practicability. The paper further explores the key challenges and future prospects of ultrasonic nondestructive testing technology, proposing that future efforts should address the impact of microscopic characteristics on sound wave transmission and the challenge of achieving high-precision sound wave velocity measurements to advance the preparation and application of large-size, high-performance ULE materials. This review constructs a multi-disciplinary perspective on the detection technology system for coefficient of thermal expansion in ULE, providing new ideas and technical references for related research.